## Fall Registration Open

If you are in Seattle or Bellevue, we have a host of great classes and circles to offer this fall, all focusing on the beauty, power, and elegance of mathematics. Saturday Classes at the PNA in Phinney Ridge This Saturday session runs for six sessions, from October 18 – November 22. This session’s topic: Games, Logic and Arithmetic. Kindergarten & 1st grade Section …

## Announcements

Note: The Math for Love newsletter does not usually get posted on the blog. If you’d like to sign up, enter your name and email in the sidebar. Here are the announcements from our last one. A Coin Problem I’ve posted one of my favorite problems of all time as this week’s NYTimes Numberplay puzzle. Consider this simple game: flip …

## Robinson Center Class Registration Open Today!

We are expanding our class offerings at the Robinson Center, with Saturday classes now available for students K-11. Registration opened today, and these classes have a way of filling up fast! Registration and class info is here: http://depts.washington.edu/cscy/programs/saturday/. The math classes we’re responsible for are below. There are also Saturday writing classes. Spring Courses  Grades K-1 and Parents Nurturing the …

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## A motivation for fractions: is it fair?

I was asked last week to teach a guest lesson for 3rd graders on fractions using Everyday Math. The book had some nice lessons, including one that involved building pattern block designs and then figuring out what fraction of them are triangles, hexagons, etc. A sweet little lesson, no complaints (though a caveat for those who use pattern blocks to …

## Math for Love activities in January

Lots in development for January, so here goes: We’re offering circles and classes all over town for kids grade K – 10, including a class for K-1 children and their parents at the Robinson Center (Nurturing the Math Instinct), and a pair of classes for 6th and 7th graders at Seattle Central Community College on Saturday mornings (Outmaneuver! and Billiard …

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## Squares of Differences III: a surprising solution

[See Squares of Differences I and Squares of Differences II, and apologies for the tardiness of the posting] I’ve learned a lot about Squares of Difference in the last months. First, they’re sometimes known as Difference Boxes, or Diffy Boxes, or sometimes Ducci Sequences, or the 4 number game, and references to them are indeed available online. However, my favorite …

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## Squares of Differences II: Changing Direction

[Note: this is a continuation to the first Squares of Differences post. Read that before continuing.] A week after introducing her class to squares of differences (see  for the first post on this lesson), one of Katherine’s students walked in with a list of squares that they claimed would continue for 20 steps before reaching all zeroes. Here’s an example …

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## Squares of Differences: subtraction practice toward a greater purpose

Here is a phenomenal lesson, accessible to any child who knows how to subtract, and compelling to everyone, up to and including professional mathematicians. Get a kid engaged in it, and they’ll do hundreds of subtraction problems without complaint, because it’s helping them solve an honest mathematical mystery. I’ve seen this idea discussed in math education circles, but I haven’t …

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